Power hammer



Sept. 6, 1932. A SCHNElDER A 1,875,939

POWER HAMMER Filed Feb. 25. 1951 l [H1/enfer.'

Patented Sept. 6, 149321 UNITED Vis'"ril'riais PATE-NT OFFICE! .,ARlI-IUR SCHNEIDER, F DUSSELDORF, GERMANY, ASSIGNOR v'lO EUIVIU'COl AKTIEN-V i i GESELLSCHAFT FUE MASCHINENBAU, OF lliEVllzl-KUSEN-SGHLEIBUSCI-I,V GERMANY, A

GER-MAN COMPANY POWER HAMMER Application ied February 25, i931, serial No. sieraden@ G ermanyrebruary 27,'1930. l

My invention relates to an improved power hammer adapted to be raised by an elastic fluid and to be lowered again in an accelerated manner, and has for its object to reduce the stress to which the piston rod of this hammer is subjected to such an extent that the piston rod will withstand the shock due to the blow without breaking and without bein@ made stronger than is necessary in order to permanently resist the forces during the raising of the hammer.

The invention consists in employing in a hammer of the type described, in connection y y with one another, a piston rod capable of moving within the tup and a cushion disposed between the piston rod and the tup and adapted to become upwardly and downwardly effective during the motion of the piston 3 rod.

By way of example, a power hammer is illustrated in the accompanying drawings, in which Figure l is a front. view, partly in section, of a power hammer, and Figure 2 is j a section of' the improved tup.

Referring to the drawings, the hammer is shown in Fig. l is provided with a frame a wherein the tup b is vertically guided in the known manner. Thel Atup Zi has a bore c through which the piston d attached to the lower end of the piston rod e can move up and down, the bore c being closed on top by a plate. The stuh'ing box L in which the piston rod e can be guided effects the permanent air-tight and steam-tight closing of the bore c. The duct c connects the space of the bore c over the piston Z with the space of the bore c under the piston d. To the lower surface of the tup the upper portion l of a die may be secured, the lower portion m of the die 4o' being attached below the tup to the anvil.

The upper end of the piston rod e carries a piston z' adapted to move up and down in the cylinder 7c sealed air-tight and steam-tight von top and below and connected with the control valve p which is capable of alternately admitting into the upper and lower portion of the cylinder 7c a fluid that is under pressure due, for example, to compressed air or O steam. This fluid may be supplied by a pipe,

not shown, which is connected at p. The

control lfvalvepp is automatically moved up and down by means of the rods v.0',:and the rods o serve for actuating the control valvey p by hand or foot. The piston rod e vand the piston e' areperforated along the central line of the piston rod e.4 The bore d leads from,

A curved lever n hugs in the usual way a face of the tup b' and is connected with the control rods og'and thus with the control valve :39.

"lh'e hammer as as follows :v i l ,'When `compressed air or steam is supplied from below'under the piston z' by the valve p,

the .piston rod e with the piston is raised until the bore al is out of communication with thel duct c and the contents-air, compressed air or steamr-of the portion of the bore c arranged above the piston Z is compressed y, to suolifan extent thatits pressure .upon the pistoi'ic is asgreat as the resistance offerfed by the tup b to its upward motion. The tupY b is then liftedl until the control valve p is closed again by the curved lever wand the action of the fluid admitted into the cylinder l: ceases. Simultaneously, compressed air or steam is admitted through the valve into" the space above thepiston The pistoni then Vdescends again with the rode and the ,tup b.' When the pressurel uponV the surface of the piston z' has increasedto the:

necessary degree, the piston z' with the piston rod eand the piston o3 will move more quickly than the tup Zi, which, however, is counteracted by the fluid flowing through the pipe q, tliefbore cf', the bore d" and theduct .ci

into the .bore c. ll/Vhen the piston d descends in thebore -c far enough to shut ofi' the bore d from the duct c', the contentsl of the bore shownand described works l c under thepi'ston d are gradually compressed andiformfa' cushion for :the motion ,offthe pistn rfo'd,., ej and' the parts connected ,there-J withlrelative to the tup Z). If the upper portion 1 ofthe die strikes the lowervportion m TheV piping g may be omitted as inthe im"-y provedform shown in Fig. 2 which is a seccome shut and opened by the piston of the tup rod during its motion within the bore of the tup.

In testimony whereof I have ailixed my signature.

ARTHUR SCHNEIDER.

tion drawn vertically to the frame or stand j as illustrated in Fig. L1, the entire hammer beingotherwise constructed exactly as shown in Fig. ll. The improved tup b shown in Fig. 2 has two bores g and f connecting'the.'v

bore c with the outer air and, whenever released bythe piston d, brings the pressure in the bore 0 on the same level as the pressure of the outerr air. Therefore, even if s 'com'-r y pressed air should'partly escape from the bore c through a leaky joint between the piston l and the bore 'cv and owing tothe leakiness of lthe stufing'box la, it will be filled up again every time before thev cushion becomes effecv tive that develops above or below the piston l in the bore '-0. At each ascent of the pis- 2,5 ton rod e acushion will therefore be created as soon as the piston 'CZ has passed beyond the Vopening g and, vice versa, on passing the y opening f. l Whenever this happens, the air compressed within the cushion tends tolpiess back the pis- `toni l with the piston rod e into their initial positions, yapproximately in the center of the length of the bore c,'and at a speed suficient to permit the two cushions to be intheir 3.5.. proper initial'state again for new'action during the neXtblow.` This arrangement sufficesv as a ruleY for this purpose.

I claim 1. A hammer adapted to be l&0-.. cel`e`rated downwardly by an elastic fluid,

comprising in'co'mbination, a'tup, a tuprod` Vwithl a piston movable within a boreof' the Y tup', an vair cushion disposed between the piston of the tup rod and the tup and adapted' 4 .5,to become upwardly and downwardly'effec# Q'tive during the motion of the piston ofthe' .tupl rod, and a plurality ofducts through the wallsl of Ythetup'between the bore of theV 'tup and the outer atmosphere, certain lof said 5,0dulcts being effective aboveand the others Y' below said piston'andadapted `to be shut and opened by the piston of the tup rod during its motion` within the .boreof the tup.

2. A hammer adapted to be raised and ac s' 55l3celerated" downwardly by an elastic fluid,

comprising, in combination, a tup, a tup rod with a'piston movable within a bore of theY tup, an air cushion disposed between thepis-` ton of the tup rod and the tup,`and a plurality 5,95 of 4ducts through the walls of the tup beraised and actween the bore of the tup and theouteratmosphere disposed above'and below the middle portion ofjthe piston of the tup rod, certain of said ductsbeing effective above and the Othersbelow said piston andv adapted to be- 

